Fcknace bukner



| HERMITTE FURNACE BURNER Aug. 16, 193s.

Fil-ed May 17, 1937 2 Sheets-Sheet l vllllllllll .Puentes Aug. 1c, 193sUNiTaD .STATT-:s

FUBNACE BURNER Y 'mais nemica, Paris, France, minor' to ,sc

clt'llateau, Paris, France,Y a corporation of France 'application may11, 1931, sei-iai No. 143,229

lin Franc May 2 3. 193s s ciiiinrii. (ci. 15s-ssi Therev exist furnacesheated by means of a liquid fuelgsuch as mazout, in which the feed ofsaid fuel is controlled through anoutilow or discharge conduit tted onthe delivery pipe of 5 the burner feed pump.

This pump is for instance a volumetric pump working at uniform speed andsupplying. consequently, a uniform total feed. TheV variation of thesection of this discharge conduit, since it permits of returning aportion of the fuel to the intake of the pump or to the feed tankthereof, permits of controlling at will the portion of the v deliverythat passes to the burners.

Therefore, in the case of a furnace fed by means of a 'single burner ora fixed number of 'burners all controlled byl the same discharge means,the useful feed of fuel supplied by said burner or burners dependsmerely upon the positlonvof said control means. Butlf the number ofburners in operation is variable, according to the working conditions ofthe system, then the total useful feed of mazout depends both upon thedegree of opening of said discharge means and upon the number of burnersin service. For

a given position of the discharge means, for instance, the usefulfeedwill be in proportion ofv the number of burners in service.

Inversely, in order to obtain the same useful' feed with differentnumbers of burners, it is necw essary to give different positions to thedischarge means. g

This may involve disadvantages, especially when the control n ieinr r isoperated by an automatic regulator. For instance, in the case of 85 aboiler furnace, the opening of the mazout discharge may be automaticallyperformed either by 'a steam pressure regulator or by a steam feedregulator, or again by any other combination. 'In these .various cases,the obtainment of the 4o same useful feed of fuel will depend uponwhether thereds la greater or smaller number'of burners in service fordifferentposiiions of the control member, that is to say for differentvalu of the control parameter, to wit pressure or feed of Now, itisgenerally desirable that the determination of this variable should bealways the same fora predetermined rate of combustion, whatever be thenumber of burners employed for obtaining this rate of combustion.. Theobject of the present invention is to provide a 'system with which thecontrol of the rate of feed of fuel is independent of the number f ofburners in service, this rate of feed being determined solely'by theposition of the regulating member which controls the discharges; fuel.

According to the essential feature of the present invention, I provide,in connection with the delivery pipe of 'the fuel pump, a number of.`discharge circuits equal to the number of burners, each of thesecircuits being-tted with a. control 5 member operated in such mannerthat, at any time, the opening of the passage is the same for all thecircuits, andwith a cut-off. member or valve adapted to be always openedor closed at the same time as the corresponding burner. i 10 Otherfeatures ofthe presentA invention will result from the followingdetailed description of a specific embodiment thereof.

A preferred embodiment of `the present 1n- 'vention will be hereinafterdescribed, with` ref-l la erence to the accompanying drawings, givenmerely byway of example, andin which: Figs. la andl 1b are respectiveportions, intended to be assembled along line a`a. of a diagrammaticalview illustrating thel general arrange- 20 ment of a system according tothe present invention.as applied to the particular case of a .boilerfurnace having four burners, .the steam pressure of the boiler beingautomatically lregulated; 25 Fig. 2 shows the curve of variation of thefuel pressure as a function of the useful feed to the furnace. i

The fuel. for instance-mazout, drawn from tank I by pump 2, is deliveredthrough pipe. 3 30 into chamber'd, and then,- through pipe 5, to aplurality of burners, for instance four in the particular case. Theseburners are designated on the drawings by reference characters6--87-,6'2-

Chamber ii is provided with discharge or return orifices, 1, 1',11",,and 1"' (the number of which is equal to the number of burners)vadapted to return to tank I a portion of the mazout present in tank- I,through return conduit 8. The useful 40 section of these dischargeorifices is controlled by the position of four adjustment needle valves9, 9',-9", and 9"' having identical profiles and which movesimultaneously under the action of a piston I0 with which they areconnected through 45 a transverse member II, in such manner that thedisplacements of these needle valves are always the same for all ofthem. These needle valves may bereplaced by any other/equivalent meansgiving, for each position of the whole, an 50 equal section of theorices 1, 1', 1" and 1'.". Finally, valves or other cut olf means I2,I2',

` I2" and IZ'" are adapted to cut off each of the burners from themazout feed pipe 5, and, on the other` hand, valves I3, i3', I3" and I3"are in- 55 I terposed between 11', 1", and 1"' and the pipe I throughwhich mazout is returned to tank I.

- and the burners lPump 291s of the'volumetric type, driven at a uniformspeed, therefore supplying a constant feed of mazoutl supposing that allthe valve I2", I2" and Il, I3', Il", Il" are open, it is clear that fora certain opening of needle valves 9 to 9" the total delivery of thepump is distributed in a given proportion between the burners and thereturn pipe 8. 'If the needle valves are closed, the whole of thedelivery of the pump passes through the burners. If, on the contrary,the needle valves are fully opened, there is substantially no feedthrough the burners. In other words, the useful fuel feed can becontrolled by determining the position of the needle valves, that is tosay the position of piston I0.

Now, it will be supposed that, without'modifying this position, some ofthe burners are brought out of service, for instance burners 6" and''",by closing valves I2 and I2. and also, simul taneously, valves I I" andI3".

It will be readily understood that the distribution of the total feedbetween the return pipe 8 the useful feed remains the same. However, `asthis useful feed now passes through two burners 6 and 8', whereas,precedingly it passed through four burners, the pressure of mazoutthrough the feed pipes and at the outlet of lthe lpump has nowincreased.

In a general manner, and supposing that for burners is used, an equalnumber of valves will be opened on the return circuits above referredto. When designating by Sn the maximum opening of each of the dischargeto 1"', the total passage for the useful feed of fuel is p.Sn and thetotal passage for the fuel returned to the tank is p.Sn.X, in which Xdesigpates the degree of opening of the control valve and Sn the maximumopening of each of the discharge passage It follows that, under theseconditions, the total feed of the pump is distributed betweenthereturned to the tank Sn and Sax..

If I keep the same-opening of the regulating o r control valves, that isto say the same value of X, but I make use of q burners instead of thetotal passages become respectively Saa and Sn.q.X. f ere ore, thedistribution of the feed proportionally to numbers v This systemtherefore ensures the independence of the control of the maxout feed,which ldepends solely upon the position of piston III and the number ofburners in service. 'I'he bringing in to, or out of, service of a burnertakes place by simultaneously opening or closing one of the 'valves I2and the corresponding valve I3 to II'", this operation having nodisturbing influence upon 1 the control of the fuel feed.

As it is generally advantageous to employ, for a given rate ofcombustion, the minimum possible number of burners permitting the flowof the lcorresponding feed of mazout, the control of the l furnace mighttake place in the following manner:

All the needle valves 9 to 9"' being fully opened, valves I2 and I l areopened, the other cut off valves remaining closed, and only burner i isIn order to Increase the rate of combusme'ans l2, lr...

6 is not changed, that is to say combustion, a number p oi' orinces orpassages 1.

useful feed and the amount pl I ` side of deformable feed is increasedby further lowering piston I 0.' the useful feed vary- The deliverypressure and according to curve A'B' of Fig. 2, and when the maximumfeed 2Q, corresponding to two burners in service, and to pressure P, hasbeen reached, the third burner is brought into service by simultaneouslyopening valves I2" and I3".

'I'he starting of the fourth in the same manner and, for the rate ofcombustion, the inverse operations are to be effected, by closingalways, simultaneously, the cut off valve controllingA the burner thatis tobe brought out of service and the cut-off valve inserted in thecorresponding return circuit. a device automatically It is possible,with such to control the position of piston I Il and of the discharge,or return, valves by means of any regulating means.

The example hereinafter described applies to the case of a boilerfurnace with adjustment of the steam pressure.

The pressure transformer I 4 is connected through a pipe I 5 with thesteam header of the The steam pressure acts upon a manometric deformablebox I6 simultaneously. .with a spring I1 and the pressure existing in asecond manometric deformable box I8.

'I'he displacements of the bottom of this deformable box are transmittedto a valve 49.

On the other hand, a pump 20 draws oil from -a tank 2| and delivers itunder pressure into pipe 25. These two orifices 2l and- 24 are definedby the position of valve I 9, in such manner that one of theni increaseswhen the other one dey creases and inversely,A which involves pressure4variations in the intermediate chamber 26., 'As this chamber is incommunication with the -inbox Il, it is clear that the system is inequilibrium when the oil pressure is equal to the dinerence between thesteam pressure and the strength of spring I1.

Finally, I obtain, in pipe 21, an oil pressure which variesl exactly inaccordance with the vari-" ations of the steam pressure. This oilpressure -acts upon piston Ill in opposition with spring 2l.-

When the amount of steam required' from the boiler increases, forinstance as a consequence of the opening of the. output passages to theutilization apparatus, the pressure in the header decreases and also theoil pressure in pipe 2l also decreases. Piston III.' therefore movesdownwardly, which closes the fourorifices 'I to 1"' the burners. yThisincrease of the fuel feed increases the production of steam in theboiler and consequently tends to reestablish the steam corresponding tothe equis Pressure to its value librium of the system.

0f course, the means for controlling the position of the burneris-enected ,y the reduction ofpushed by its spring I'I,

and increases the feed to needle valves, according to the de- 76 piston35', which Q Thiscontrol of aismva -sired result, are not in any waylimited to this particular example. For instance, always in the case ofa boiler, I may make use of a steam feed regulator, either alone or incombination with a pressure regulator.

The control of the number of, burners in service may. also be obtainedautomatically. The following device constitutes an example of automaticcontrol starting a new burner every time;

those in service reach their maximum and, inversely, stopping a becomespossible to ensure system with a number of burners reduced by one.

For this purpose, a Venturi nozzle in pipe 5 betweenthe discharge needlevalves and the burners gives a pressure drop which is a function of theuseful feed to the burners, especially forrates of feed of Q, 2Q, 3Q,corresponding respectively to the maximum output of one, two, or threeburners, or to pressure drops equal to H', H", H'". This pressure dropacts through two conduits 3h, connected respectively to pipe 5 onopposite sides of pistons 3|', 3|", 32', 32", 32"'. respective strengthsthat they are successively overcome by respective values of the pressure,drop equal to HUH", H'". E

These pistons control the oil distributors 33', 33", 33"', connected onthe other hand to pistons 34'., 3d", 36" which control valves I2', I2",I2"

- and to pistons 35', 35",`35"' which control valves I3', i3", I".

In the embodiment illustrated by Fig. i, burner 6' is shown in service.2|! into pipe 22 enters the distributor 33' through conduit 36' andleaves it through conduit 3 1'. It exerts its pressure through pipeS'upon piston 3ft', which compresses the opposing spring 39' and opensvalve I2'.

Through pipe Q0', this oil pressure v,acts upon output,

valve i3. Burners t" ing out of service, the position of the'respectiveoil distributors 33" and 33"' corresponding thereto connecting pipes 31"and 31"' with the discharge pipes 62" and 42"' turns to the tank 2l.

Springs 39", 39"' on the one hand and 4I", il i on the other handareexpanded, closing the corresponding valves.

The operation of this system takes place in the following manner:

Burner 5 andvalves I2 and I3 are still controlled manually for startingthe furnace. When the output of this burner reaches the maximum value Q,the pressure drop in venturi 29 reaches value H' and piston 3l' ismoved, together with its oil distributor, which I3' and brings thesecond burner E' into service.

If the fuel feed still increases, when it reaches the value 2Q, thepressure drop in venturi 29 reaches value H". Piston 3 I then moves,bringing burner 8" into service, and so on.

lnversely, if the fuel feed is decreased, when its value 'reaches 3Q,then 2Q, and finally Q, respectively, the pressure drop in venturi 29passes. through decreasing values H'", H", H', respectively, and springs32"', 32", 32' successively move back the corresponding pistons, whichybrings out of service burners 6"', i" and 8', successively.

the number of burners in serv- L ice is given merely by way of exampleand it 795 should be weu understood that the invention is burner everytime it theworking of the 2s, inserted the venturi, and acting upon3I'", in opposition with springs These springs are lmade of suchv Theoil delivered by pump f crushes spring LI and opens and B!" are shown asbethrough which oil re-\ said return circuits respectively,

opens valves I2 and not in any way limited to this particular .examplesince, for instance, instead of the venturi I might make use of any feedmeter, or again I might employ, as control parameter, a variable otherthan the feed of mazout.

For instance, I might make use, for this pur-.

use of the mazout pressure. Thedistributor 33' pose, of thestearnpressure. I may also 'make is then controlled by a piston whichmoves when f the mazout pressure exceeds value P (Fig. 2) and comesbacl'r to its position when said pressure drops below value p.

I n a general manner, while' I have, in the above description, disclosedwhat I deem' to be practical and elcient embodiments lof the presentinvention, it should be well understood that I do not wish tobe limitedthereto as there might be 4changes made in the arrangement, dispositionandform of the parts without departing from the principle of the presentinvention as comprehended within the scope of the appended claims.

What I claim is:

1..In a system including a number of liquid outlet means, and a vpumpfor supplying liquid under pressure to said means in parallel, a controldevice which comprises, in combination, an equal number of return liquidcircuits inserted in parallel between the delivery of said pump and theintake thereof, variable passage control means in said return circuitsrespectively, means for simultaneously operating said passage control sothat all of said control means always have the same position in all ofsaid return circuits respectively, valve means for controlling said-device which comprises, in combination, an equal,

circuits inserted in parj number of liquid return allel between thedelivery of said pump and the intake thereof, variable passagecontrol'means in means for similitaneously operating said passagecontrol means so that all of them always have the ,same position in allof said return circ'uitsr'espectively, valve means for controlling said'burners, and cut-oil' valve means` in each of said return circuits, andmeans interconnecting each of said last mentioned valve means withoneIof the first means with one of 4the first mentioned valve means, forcausing them mentioned valve means, respectively, for causing, I them tobe operated simultaneously and in the 'I same direction.

3. In a system including a number of fuel burners, a fuel tank, and apump for supplying fuel from said tank under pressure to' said burnersin parallel, a control system which comprises, in combination, a chambermounted on the delivery of said pump, return circuits, equal to thenumber of'fuel burners, inserted in parallel between said chamber andsaid tank, a plurality of needle valves" for controlling the -ilowthrough said liquid circuits, respectively, means for simultaneouslyoperating said needle valves so is aways the same for all of them, forcontrolling said in each of said return circuits, and meansinterconnecting each of said last mentioned valve a number of liquidmeans with one of the iirst mentioned valve means, respectively, so asto cause them to be opetxi-ated simultaneously and in the same di-` recon.

said furnace, a fuel tank, and a pump for supplying fuel from said tankunder pressure to said burners, in parallel, a control device whichcomprises, in combination, a chamber mounted on the delivery of saidpump, a number of fuel return circuits, equ'al to the number of burners.inserted in parallel between said chamber and said tank, a plurality ofneedle valves for controlling the flow of fuel through said fuel re--turn circuits, respectively, adapted to determine always the samepassage .through all of said circuits, respectively, means,automatically operative in response to the working conditionsfin saidboiler, for simultaneously actuating all of said needle valves, 'cut-oi!valve means for controlling 'said burners, and cut-0U valve means ineach of said return circuits, each of said last mentioned valve meansbeing associated with one -of the first mentioned valve means,respectively,

to be operated simultaneously, therewith and in the same direction.

5. In a system including a boiler, a furnace for said boiler, a numberof fuel plying fuel from -said tank under pressure to said burners, inparallel, a 'control device which comprises, in combination, a chambermounted on the delivery of said pump, a number of fuel return conduits,equal to the number of burners,

inserted in parallelbetween' said chamber and said tank, a plurality oflneedle valves for controlling the flow of fuel through said fuel returnconduits, respectively, adapted to determine always the samepassagethrough all of said respective circuits, an oil circulationsystem, means forautomatically controlling the pressure through at leasta 4portion of 4said circulation system in" accordance with variations ofthe steam 4. In a system including a boiler, a furnace i'or' said boileranda numberl of fuelv burners for the flow of fuel through burners forlVsaicl furnace, a fuel tank, and a pump for suppressure in said boiler,means operative by said oil pressure for simultaneously aetuating-all-ofsaid needle valves, cut-oil' valve means for controlling said `burners,and cut-off valve means in each lof said fuel return conduits, each ofsaid last mentioned valve means one of the first mentioned valve means,respectively, `to be operated simultaneously therewith, and in the samedirection.v

6. In a system including a boiler, a furnace for said boiler, a numberof fuel burners for said furnace, a fuel tank, and a pump for supplyingfuel from said .tanki under pressure to said burners, in parallel,acontrol device which comprises, in combination, a chambery mounted onthe delivery of said pump, a number of fuel return conduits equal to thenumber of burners, inserted in parallel between said chamber and saidbeing associated with tank, a plurality of needle valveslforcontrolling,

said fuel return conduits respectively, adapted to determine always thesame passage through all of said respective circuits, means forsimultaneously actuating all oi' said needle valves, cut-oil valve meansfor controlling said burners, respectively, cut-ofi valve means in eachof said return conduits, each of said last mentioned valve means beingassociated with one of the rst mentioned valve means, respectively, tobe operated simultaneously therewith and in the samel direction, andmeans, operative by the working conditions, for successively opening andclosingsaid burners in an automatic manner.

7. A system according to claim 6in which said last mentioned means areoperative 'in response to variations of the feed of fuel from saidv pumpto said burners.

8. A system Kaccordingt claim 6 in which said last mentionedmeans-include a Venturi element inserted between saidpump and saidburners, and meansy operative by the pressure drop produced by saidvVenturi element forJ controllingsaid first mentioned cut-oil valvemeans.

LOUIS HERMII'IE.

